Grating sheet, lcd device and methods for manufacturing grating sheet and lcd panel

ABSTRACT

A grating sheet, a LCD device and methods for manufacturing the grating sheet and a liquid crystal display panel are provided. The grating sheet comprises a plurality of primary color gratings in parallel, each of which comprises a red R sub-grating, a green G sub-grating and a blue B sub-grating in parallel, and each sub-grating comprises an opening area and a reflective region disposed around the opening area and corresponds to a pixel unit on a sub-array substrate. The grating sheet, the liquid crystal display panel and methods for manufacturing the grating sheet and a liquid crystal display panel may be applicable to a system with a liquid crystal display.

BACKGROUND

Embodiments of the disclosure relate to a grating sheet, a liquidcrystal display (LCD) device, and methods for manufacturing a gratingsheet and a LCD panel.

As shown in FIG. 1, an existing LCD device comprises a backlight module11 and a liquid crystal cell 12, which comprises a lower polarizing film121, a thin film transistor (TFT) array substrate 122, a liquid crystallayer 123, a color filter substrate 124 and an upper polarizing film121. A liquid crystal display panel comprises the TFT array substrate122, the liquid crystal layer 123 and the color filter substrate 124.The backlight module 11 provides a white light source, and the lightemitted from the backlight module 11 first passes through the lowerpolarizing film 121 so as to become polarized light, then sequentiallypasses through the array substrate 122, the liquid crystal layer 123 andthe color filter substrate 124 and becomes R (red), G (green) and B(blue) primary color light using R, G and B sub-pixels on the colorfilter substrate 124, and finally exits from the upper polarizing film125. Images may be displayed by controlling orientation angles of theliquid crystal molecules in the liquid crystal layer 123 fortransmitting light.

A conventional LCD device generates the R, G, B primary color light byusing the R, G, B sub-pixels on a color filter substrate comprising aplurality of R, G, B sub-pixels disposed parallel with one another andin an array, as shown in FIG. 2. Black matrix regions are formed aroundopening areas of the R, G, B sub-pixels for blocking light, thus lightwill be totally absorbed when the light is incident onto the blackmatrix region, therefore part of light emitted from the backlight modulemay be wasted so that a utilization ratio of the light is relativelylow.

SUMMARY

Embodiments of the present application provide a grating sheet, a LCDdevice and methods for manufacturing the grating sheet and a liquidcrystal display panel, which can prevent part of light emitted from thebacklight module from being absorbed by a black matrix and thus wastedso that a utilization ratio of the light is relatively high.

According to an aspect of the disclosure, a grating sheet is provided,which comprises a plurality of primary color gratings disposed parallelwith one another, wherein each primary color grating comprises a red (R)sub-grating, a green (G) sub-grating, and a blue (B) sub-gratingparallel with one another, and wherein each sub-grating comprises anopening area with a metal layer for diffraction therein and with areflective region disposed around and corresponds to a pixel unit.

According to an aspect of the disclosure, a liquid crystal display (LCD)device is provided, comprising: a liquid crystal cell, comprising anupper polarizing film, a liquid crystal display panel, and a bottompolarizing film from top to bottom, wherein the liquid crystal displaypanel comprises an array substrate, an opposing substrate and a liquidcrystal layer interposed between the array substrate and the opposingsubstrate; and the above-described grating sheet, wherein the gratingsheet is provided at a light exiting side of the backlight module.

According to an aspect of the disclosure, a method for manufacturing agrating sheet is provided, wherein the method comprises: sequentiallydepositing a silicon nitride film on a base substrate, forming a red (R)sub-wire grating, a green (G) sub-wire grating and a blue (B) sub-wiregrating by a patterning process and then coating a metal film on thebase substrate to form a red (R) sub-grating, a green (G) sub-gratingand a blue (B) sub-grating parallel with one another; and forming areflective film on the base substrate, and forming a reflective regionaround the opening area of each sub-grating by a patterning process.

According to an aspect of the disclosure, a method for manufacturing aliquid crystal display panel is provided, wherein it comprise: formingan opposing substrate with only a transparent conductive film depositedthereon; forming an array substrate on which a data line and a gate lineare crosses with each other and define a pixel unit; forming the gratingsheet according to embodiments of the disclosure, wherein the gratingsheet is formed on a glass substrate, an array substrate or an opposingsubstrate; attaching the array substrate and the grating sheet orattaching the opposing substrate and the grating sheet when the gratingsheet is formed on the glass substrate; and when the grating sheet isformed on the array substrate or the opposing substrate, attaching thearray substrate and the opposing substrate.

Further scope of applicability of the present disclosure will becomeapparent from the detailed description given hereinafter. However, itshould be understood that the detailed description and specificexamples, while indicating preferred embodiments of the disclosure, aregiven by way of illustration only, since various changes andmodifications within the spirit and scope of the disclosure will becomeapparent to those skilled in the art from the following detaileddescription.

BRIEF DESCRIPTION OF THE DRAWINGS

The present disclosure will become more fully understood from thedetailed description given hereinafter and the accompanying drawingswhich are given by way of illustration only, and thus are not limitativeof the present disclosure and wherein:

FIG. 1 is a schematic structural view of the LCD device in the relatedart.

FIG. 2 is a top view of the opposing substrate in the LCD device asshown in FIG. 1.

FIG. 3 is a schematic structural view of a grating sheet according to anembodiment of the present disclosure.

FIG. 4( a) is a first cross-sectional view of the grating sheet as shownin FIG. 3.

FIG. 4( b) is a second cross-sectional view of the grating sheet asshown in FIG. 3.

FIG. 5( a) is a schematic structural view of the LCD device according toan embodiment of the disclosure.

FIG. 5( b) is a schematic structural view of the LCD device according toanother embodiment of the disclosure.

FIG. 5( c) is a schematic structural view of the LCD device according toanother embodiment of the disclosure.

FIG. 5( d) is a schematic structural view of the LCD device according toanother embodiment of the disclosure.

FIG. 5( e) is a schematic structural view of the LCD device according toanother embodiment of the disclosure.

FIG. 5( f) is a schematic structural view of the LCD device according toanother embodiment of the disclosure.

FIG. 6 is a schematic structural view of an exemplary backlight modulein the LCD device as shown in FIGS. 5( a) to 5(f).

FIG. 7 is a schematic structural view of another exemplary backlightmodule in the LCD device as shown in FIGS. 5 (a) to 5(f).

FIGS. 8( a) to 8(e 2) show the process of manufacturing a grating sheetaccording to still another embodiment of the disclosure.

DETAILED DESCRIPTION

To make objectives, technical solutions and advantages provided by theembodiments of the present disclosure more clearly, a clear and fulldescription will be made to the technical solutions of embodiments ofpresent disclosure hereinafter in connection with the accompanyingdrawings. Apparently, rather than all the embodiments, embodiments to bedescribed are only a part of embodiments of present disclosure. Based onthe embodiments of the present disclosure, other embodiments conceivedby those skilled in the art without inventive work would fall within thescope of present disclosure.

Embodiments of the disclosure provides a grating sheet, a liquid crystaldisplay (LCD) device and the method for manufacturing the grating sheetand the liquid crystal display panel to prevent part of light emittedfrom a backlight module from being absorbed by a black matrix region andthus being wasted, which causes a relatively low utilization ratio.

As shown in FIG. 3, a grating sheet provided by an embodiment of thedisclosure comprises a plurality of primary color grating 31 disposedparallel with one another, and each primary color grating 31 comprisesan R (red) sub-grating 311, a G (green) sub-grating 312 and a B(blue)sub-grating 313 disposed parallel with one another. As shown inFIGS. 4( a) to 4(b), each sub-grating 41 comprises an opening area 411with a metal layer for diffraction therein and a reflective region 412disposed around the opening area 411. Each of the sub-gratingcorresponds to a pixel unit on an array substrate.

In the present embodiment, the reflective region may be a specular (ormirror) type reflective region as shown in FIG. 4( a) or a prism typereflective region as shown in FIG. 4(b). For example, the reflectiveregion is a prism type reflective region such that the light intensityreflected from the reflective region is uniform.

According to the optical principle, gratings with different widths andintervals can be used for selecting light having different wavelengths,that is, for transmitting light having specific wavelengths. The R, G, Bprimary color light required for the LCD device for display can beaccordingly obtained by adjusting the design parameters of gratingsheets based on such optical principle. In the present embodiment, theR, G, B primary color light may be selectively transmitted by usingsub-gratings having the same period length but different opening areawidths, so as to form an R sub-grating, a G sub-grating and a Bsub-grating. For example, if the metal layer for diffraction is analuminum metal layer, the design parameters of the grating sheet may bedetermined as follows:

R sub-grating: l=0.813 um, Φ=20%, t=80 nm, d=20 nm;

G sub-grating: l=0.813 um, Φ=36%, t=60 nm, d=40 nm;

B sub-grating: l=0.813 um, Φ=47%, t=40 nm, d=60 nm;

wherein “l” is a period length of a sub-grating, “Φ” is a duty cycle andΦ=w/l, “w” is an opening width of a sub-grating opening area, “t” is athickness of the metal layer for diffraction on the sub-grating, and “d”is an interval between the opening area and the reflective region.

It should be noted that the design of the R, G, B sub-gratings are notlimited to the above-described one. In another example, the design mayinclude the same period length, the same duty cycle and differentmaterial for forming the metal layer so as to achieve R, G, Bsub-gratings, and unnecessary details will not be given here forsimplicity. For example, the thickness of the metal layer of the Rsub-gratings is in the range of 75-85 nm; the thickness of the metallayer of the G sub-gratings is in the range of 55-65 nm; and thethickness of the metal layer of the B sub-gratings is in the range of35-45 nm; the material of the metal layers of the sub-gratings may bealuminum, copper, chromium, and the like.

Since the grating sheet provided by embodiment of the disclosurecomprises a plurality of parallel disposed primary color gratingscomprising an R (red) sub-grating, a G (green) sub-grating and a B(blue) sub-grating, each of which comprises an opening area and areflective region disposed around the opening area and corresponds to apixel unit on the array substrate, thereby the grating sheet can displayR, G, B colors. Since each sub-grating further comprises a reflectiveregion so that the light emitted from the backlight module and notpassing through the grating sheet is reflected from the reflectiveregion back to the backlight module, and further reflected to thegrating sheet by the backlight module, thereby the light which does notpass through the grating sheet initially can be utilized again; thisconfiguration can solve the problem that a portion of light emitted fromthe backlight module is be absorbed by a black matrix region and thuswasted, which causes a relatively low utilization ratio.

As shown in FIGS. 5( a)-5(b), a LCD device provided by an embodiment ofthe disclosure comprises a backlight module 51 and a liquid crystal cell52 comprising a lower polarizing film 521, a thin film transistor arraysubstrate 522, a liquid crystal layer 523, an opposing substrate 524 andan upper polarizing film 525. The TFT array substrate 522, the liquidcrystal layer 523, and the opposing substrate 524 constitute a liquidcrystal display panel; the liquid crystal layer 523 is interposedbetween the substrates provided opposite to each other. The LCD devicefurther comprises a grating sheet 53 provided by aforesaid embodiment,which is provided at a light exiting side of the backlight module 51.

According to one embodiment of the disclosure as shown in FIG. 5( a),the grating sheet 53 is provided between the backlight module 51 and thelower polarizing film 521. The backlight module 51 provides a whitelight source, and light emitted from the backlight module 51 firstpasses through the grating sheet 53 to obtain R, G, B primary colorlight, wherein the light which does not pass through the grating sheet53 is reflected back to the backlight module 1 and then for example aprism film in the backlight module 11 reflects the light, reflected backfrom the grating sheet 53, to the grating sheet 53 again. The R, G, Bprimary color light obtained by passing through the grating sheet 53then passes through the lower polarizing film 521 to be changed intopolarized light, then the array substrate 522, the liquid crystal layer523, and the opposing substrate 524 with only a transparent conductivelayer disposed thereon, and finally exits from the upper polarizing film525. Images can be displayed by controlling orientation angles of theliquid crystal molecules in the liquid crystal layer 523 duringtransmitting light.

According to another embodiment of the disclosure as shown in FIG. 5(b), the grating sheet 53 is provided between the lower polarizing film521 and the liquid crystal display panel. The backlight module 51provides a white light source, and light emitted from the backlightmodule 51 first passes through the lower polarizing film 521 to bechanged into polarized light, then the polarized light passes throughthe grating sheet 53 to obtain R, G, B primary color light, wherein thelight which does not pass through the grating sheet 53 is reflected backto the backlight module 51 and then for example a prism film in thebacklight module 51 reflects the light, reflected back by the gratingsheet 53, to the grating sheet 53 again. The R, G, B primary color lightobtained by the grating sheet 53 passes through the array substrate 522,the liquid crystal layer 523, and the opposing substrate 524 with only atransparent conductive layer disposed thereon, and finally exits fromthe upper polarizing film 525. Images can be displayed by controllingorientation angles of the liquid crystal molecules in the liquid crystallayer 523 during transmitting light.

According to another embodiment of the disclosure as shown in FIG. 5(c), the grating sheet 53 is provided between the array substrate 522 andliquid crystal layer 523 of the liquid crystal display panel. Thebacklight module 51 provides a white light source, and light emittedfrom the backlight module 51 first passes through the lower polarizingfilm 521 to be changed into polarized light, and then passes through thearray substrate 522, the grating sheet 53, the liquid crystal layer 523and the opposing substrate 524 to obtain the R, G, B primary color lightwith the grating sheet 53, wherein the light which does not pass throughthe grating sheet 53 is reflected back to the backlight module 51 andthen for example a prism film in the backlight module 51 reflects thelight, reflected back by the grating sheet 53, to the grating sheet 53again; and the light finally exits from the upper polarizing film 525.Images can be displayed by controlling orientation angles of the liquidcrystal molecules in the liquid crystal layer 523 during transmittinglight.

According to another embodiment of the disclosure as shown in FIG. 5(d), the grating sheet 53 is provided between the opposing substrate 524and liquid crystal layer 523 of the liquid crystal display panel. Thebacklight module 51 provides a white light source, and light emittedfrom the backlight module 51 first passes through the lower polarizingfilm 521 to be changed into polarized light, and then passes through thearray substrate 522, the liquid crystal layer 523, the polarizing film53 and the opposing substrate 524 to obtain the R, G, B primary colorlight with the grating sheet 53, wherein the light which does not passthrough the grating sheet 53 is reflected back to the backlight module51 and then for example a prism film in the backlight module 51 reflectsthe light, reflected back by the grating sheet 53, to the grating sheet53 again; and finally exits from the upper polarizing film 525. Imagescan be displayed by controlling orientation angles of the liquid crystalmolecules in the liquid crystal layer 523 during transmitting light.

According to another embodiment of the disclosure as shown in FIG. 5(e), the grating sheet 53 is provided between the liquid crystal displaypanel and the upper polarizing film 524. The backlight module 51provides a white light source, and the light emitted from the backlightmodule 51 first passes through the lower polarizing film 521 to bechanged into polarized light, next passes through the array substrate522, the liquid crystal layer 523, and the opposing substrate 524 withonly one transparent conductive layer disposed thereon, and then throughthe grating sheet 53 to obtain the R, G, B primary color light, whereinthe light which does not pass through the grating sheet 53 is reflectedto the backlight module 11 and for example the prism film in thebacklight module 11 reflects the light, reflected back by the gratingsheet 53, to the grating sheet 53 again, and then the R, G, B primarycolor light which is obtained by the grating sheet 53 finally exits fromthe upper polarizing film 525. Images can be displayed by controllingorientation angles of the liquid crystal molecules in the liquid crystallayer 523 during transmitting light.

According to another embodiment of the disclosure as shown in FIG. 5(f), the grating sheet 53 is provided at the light exiting side of theupper polarizing film 524. The backlight module 51 provides a whitelight source, and the light emitted from the backlight module 51 firstlypasses through the lower polarizing film 521 to be changed intopolarized light, then passes through the array substrate 522, the liquidcrystal layer 523, and the opposing substrate 524 with only onetransparent conductive layer disposed thereon, exits from the upperpolarizing film 525, and finally passes through the grating sheet 53 toobtain R, G, B primary color light, wherein the light which does notpass through the grating sheet 53 is reflected to the backlight module51 and then for example the prism film therein reflects the light,reflected back by the grating sheet 53, to the grating sheet 53 again.Images can be displayed by controlling orientation angles of the liquidcrystal molecules in the liquid crystal layer 523 during transmittinglight.

Preferably, the grating sheet 53 is disposed between the light incidentside of the liquid crystal layer and the light exiting side of thebacklight module in the liquid crystal display panel, as shown in FIGS.5( a)-5(c), thereby preventing part of the light emitted from thebacklight module from passing through the liquid crystal layer twice tobe reflected onto the backlight module, which may cause the lightconfusion due to the light reversion by the liquid crystal layer.

It should be noted that the above described embodiments are explained bytaking the TFT array substrate of the liquid crystal display panel asthe light incident side of the liquid crystal display panel as anexample; however, it can also be explained by taking the opposingsubstrate in the liquid crystal display panel as the light incident sideof the liquid crystal display panel as an example where the light pathis similar to that in the aforesaid embodiments, which will not bedescribed in detail here for simplicity. If the opposing substrateencounters the light emitted from the backlight module before thegrating sheet, the opposing substrate is only disposed with atransparent conductive layer.

As shown in FIG. 6, the backlight module comprises a reflective plate61, a light guide plate 62, a diffuser plate 63, a prism film 64 and aprotection film 65 from bottom to top in order; a light source 66 isdisposed on a side of the light guide plate 62 or under the light guideplate 62. The light reflected back by the grating sheet may be reflectedto the upper grating sheet again by the prism film 64 of the backlightmodule; however, the reflectivity of the prism film 64 generally islower than that of the planar mirror. Furthermore, in order that thelight reflected from the reflective region may be more effectivelyutilized again, as shown in FIG. 7, a reflective film 7 may be disposedbetween then protection film 65 and the prism film 64 of the backlightmodule. In another example, in order to reduce cost, the light exitingside surface of the protection film 65 of the backlight module in FIG. 6may be subject to a mirror finish treatment so that the light exitingside surface of the protection film 65 of the backlight module is of amirror type surface.

According to the LCD device provided by the embodiment of thedisclosure, since the grating sheets comprise a plurality of paralleldisposed primary color gratings comprising an R (red) sub-grating, a G(green) sub-grating and a B (blue) sub-grating, each of which comprisesan opening area and a reflective region disposed around the opening areaand corresponds to a pixel unit on the array substrate, thereby thegrating sheets can display R. G, B colors. Since each sub-gratingfurther comprises a reflective region so that the light emitted from thebacklight module and then not passing through the grating sheet isreflected from the reflective region onto the backlight module, andfurther reflected to the grating sheet by the backlight module, thus thelight which does not pass through the grating sheets initially can beutilized again, preventing part of the light emitted from the backlightmodule from being absorbed by the black matrix region and thus wastedand causing a low utilization ratio.

A method for manufacturing the grating sheet according to an embodimentof the disclosure comprises the following steps.

Step 801, sequentially depositing a silicon nitride film on a basesubstrate, forming an R (red) sub-wire grating, a G (green) sub-wiregrating, and a B (blue) sub-wire grating by a patterning process andthen coating a metallic film on the substrate to form an R (red)sub-grating, a G (green) sub-grating, and a B (blue)sub-grating parallelwith one another.

In the present embodiment, the base substrate may be a transparentsubstrate such as a glass substrate or a plastic substrate, an opposingsubstrate only with a transparent conductive film deposited thereon, ora finished array substrate. In the present embodiment, the metallic filmfor diffraction may be an aluminum metallic film which has a highextinction ratio and a high luminous flux, and the design parameters ofthe grating sheet are as follows:

R sub-grating: l=0.813um, Φ=20%, t=80 nm, d=20 nm;

G sub-grating: l=0.813um, Φ=36%, t=60 nm, d=40 nm;

B sub-grating: l=0.813um, Φ=47%, t=40 nm, d=60 nm;

wherein “l” is a period length of a sub-grating, “Φ” is a duty cycle andΦ=w/l. “w” is an opening width of a sub-grating opening area, “t” is athickness of the metal layer for diffraction on the sub-grating, and “d”is an interval between the opening area and the reflective region.

Step 802, depositing a reflective film on the base substrate, forming areflective region by a patterning process, wherein the reflective regionis disposed around the opening area of each sub-grating.

Another method for manufacturing the grating sheet according to anotherembodiment of the disclosure comprises the following steps.

As shown in FIG. 8( a), firstly, depositing a silicon nitride film 901on a base substrate 9 by chemical vapor deposition (CVD) process, andthen spinning coating a layer of photoresist 902 on the silicon nitridefilm 901.

As shown in FIG. 8( b), next, forming a red R sub-wire grating 903 by anexposure, developing and etching process, and then removing theremaining photoresist 902.

As shown in FIG. 9( c), then repeating the steps as shown in FIGS. 8( a)and 8(b) on the base substrate to form a G sub-wire grating 904 and a Bsub-wire grating 905 in sequence.

As shown in FIG. 9( d), forming an aluminum metal film 906 on thesurface of the substrate for example by a magnetron sputtering apparatusto form an R sub-grating 903, a G sub-grating 904 and a B sub-grating905 parallel with one another.

As shown in FIGS. 8( e 1) and 8(e 2), finally, depositing a reflectivefilm on the substrate, and then forming a reflective region 907 aroundthe opening area of each sub-grating by a patterning process.

Depositing a reflective film on the base substrate by a patterningprocess to form a reflective region as shown in FIG. 8( e 1) for examplecomprises the following steps: depositing a reflective film on thesubstrate; spinning coating a photoresist film on the reflective film;exposing an opening area of each sub-grating by performing an exposure,develop and etching process to the base substrate and then removing theremaining photoresist on the substrate.

Or, depositing a reflective film on the substrate and forming areflective region by a patterning process as shown in FIG. 8( e 2) forexample comprises: stamping by using a mold with prism patterns to forma prism type reflective film before spinning coating a photoresist filmon the reflective film in addition to the steps as shown in FIG. 8( e1). Thus the light intensity reflected from the reflective region isuniform.

It should be noted that the substrate may be a transparent substratesuch as a glass substrate or a plastic substrate, an opposing substrate,or an array substrate. If the base substrate is an opposing substrate,the opposing substrate is only with a transparent conductive filmdeposited thereon. If the base substrate is an array substrate, themethod further comprises depositing a transparent conductive film on thearray substrate before sequentially depositing the silicon nitride filmon the substrate.

According to the grating sheet, the LCD device and the method formanufacturing the grating sheet and the liquid crystal display panelprovided by embodiments of the disclosure, since the grating sheetcomprise a plurality of parallel disposed primary color gratingscomprising an R (red) sub-grating, a G (green) sub-grating and a B(blue) sub-grating, each of which comprises an opening area and areflective region disposed around the opening area and corresponds to apixel unit on the array substrate, thereby the grating sheet can displayR, G, B colors. Since each sub-grating further comprises a reflectiveregion so that the light emitted from the backlight module and notpassing through the grating sheet is reflected from the reflectiveregion onto the backlight module and further reflected to the gratingsheet by the backlight module, thereby the light which does not passthrough the grating sheet initially can be utilized again, which cansolve the problem that part of the light emitted from the backlightmodule may be absorbed by the black matrix region and thus wasted andcauses a low utilization ratio.

A method for manufacturing the liquid crystal display panel according toan embodiment of the disclosure comprises the following steps.

Step 1001, forming an opposing substrate on which only a transparentconductive film is formed.

Step 1002, forming an array substrate, wherein data lines and gate linesare crosses with each other and thus define pixel units on the arraysubstrate.

Step 1003, forming an above-mentioned grating sheet, wherein the gratingsheet is formed on a transparent substrate, the array substrate or theopposing substrate.

Step 1004, when the grating sheet is formed on the transparentsubstrate, attaching together the array substrate and the grating sheetor attaching together the opposing substrate and the grating sheet.

Step 1005, when the grating sheet is formed on the array substrate orthe opposing substrate, attaching together the array substrate and theopposing substrate.

According to the method for manufacturing the liquid crystal displaypanel according to the embodiment of the disclosure, since the gratingsheet comprise a plurality of parallel disposed primary color gratingscomprising an R (red) sub-grating, a G (green) sub-grating and a B(blue) sub-grating, each of which comprises an opening area and areflective region disposed around the opening area and corresponds to apixel unit on the array substrate, thereby the grating sheet can displayR, G, B colors. Since each sub-grating further comprises a reflectiveregion, so that the light emitted from the backlight module and notpassing through the grating sheet initially is reflected from thereflective region onto the backlight module and further reflected to thegrating sheet by the backlight module again, thereby the light whichdoes not pass through the grating sheet initially can be utilized again,which can solve the problem that part of the light emitted from thebacklight module may be absorbed by the black matrix region and wastedand causes a relatively low utilization ratio.

The grating sheet, the LCD device and methods for manufacturing thegrating sheet, liquid crystal display panel according to embodiments ofthe disclosure may be applied to a system having a liquid crystaldisplay.

It should be appreciated that the embodiments described above areintended to illustrate but not limit the present disclosure. Althoughthe present disclosure has been described in detail herein withreference to the preferred embodiments, it should be understood by thoseskilled in the art that the present disclosure can be realized withdifferent material and equipment as necessary, and that variousmodification and equivalents thereof can be made herein withoutdeparting from the spirit and scope of the present disclosure.

1. A grating sheet comprising a plurality of primary color gratingsdisposed parallel with one another, wherein each primary color gratingcomprises a red (R) sub-grating, a green (G) sub-grating, and a blue (B)sub-grating parallel with one another, and wherein each sub-gratingcomprises an opening area with a metal layer for diffraction therein andwith a reflective region disposed around and corresponds to a pixelunit.
 2. The grating sheet according to claim 1, wherein the reflectiveregion is a mirror surface type reflective region.
 3. The grating sheetaccording to claim 1, wherein the reflective region is a prismreflective region.
 4. The grating sheet according to claim 1, whereinthe metal layer for diffraction is an aluminum metal layer.
 5. Thegrating sheet according to claim 1, wherein, R sub-grating comprises:l=0.813 um, Φ=20%, t=80 nm, d=20 nm; G sub-grating comprises: l=0.813um, Φ=36%, t=60 nm, d=40 nm; and B sub-grating comprises: l=0.813 um,Φ=47%, t=40 nm, d=60 nm; wherein “l” is a period length of eachsub-grating, Φ is a duty cycle and Φ=w/l, “w” is an opening width ofeach sub-grating opening area, “t” is a thickness of the metal layer fordiffraction on the sub-grating, and “d” is an interval between theopening area and the reflective region.
 6. The grating sheet accordingto claim 1, wherein, a thickness of the metal layer of the Rsub-gratings is in the range of 75-85 nm; a thickness of the metal layerof the G sub-gratings is in the range of 55-65 nm; and a thickness ofthe metal layer of the B sub-gratings is in the range of 35-45 nm.
 7. Aliquid crystal display (LCD) device, comprising: a liquid crystal cell,comprising an upper polarizing film, a liquid crystal display panel, anda bottom polarizing film from top to bottom, wherein the liquid crystaldisplay panel comprises an array substrate, an opposing substrate and aliquid crystal layer interposed between the array substrate and theopposing substrate; a backlight module, disposed behind the liquidcrystal cell; and the grating sheet according to claim 1, wherein thegrating sheet is provided at a light exiting side of the backlightmodule.
 8. The LCD device of claim 7, wherein the grating sheet isprovided between the backlight module and the lower polarizing film; orthe grating sheet is provided between the lower polarizing film and theliquid crystal display panel; or the grating sheet is provided betweenthe array substrate and the liquid crystal layer of the liquid crystaldisplay panel; or the grating sheet is provided between the opposingsubstrate and the liquid crystal layer of the liquid crystal displaypanel; or the grating sheet is provided between the liquid crystaldisplay panel and the upper polarizing film; or the grating sheet isprovided at a light exiting side of the upper polarizing film.
 9. TheLCD device of claim 8, wherein a reflective film is disposed between aprotection film and a prism film of the backlight module, or a lightexiting side surface of the protection film of the backlight module isof a mirror surface.
 10. The LCD device according to claim 8, wherein atransparent conductive layer is formed on the opposing substrate of theliquid crystal display panel.
 11. The LCD device according to claim 9,wherein a transparent conductive layer is formed on the opposingsubstrate of the liquid crystal display panel.
 12. A method formanufacturing a grating sheet, comprising: sequentially depositing asilicon nitride film on a base substrate, forming a red (R) sub-wiregrating, a green (G) sub-wire grating and a blue (B) sub-wire grating bya patterning process and then coating a metal film on the base substrateto form a red (R) sub-grating, a green (G) sub-grating and a blue (B)sub-grating parallel with one another; and forming a reflective film onthe base substrate, and forming a reflective region around the openingarea of each sub-grating by a patterning process.
 13. The methodaccording to claim 12, wherein depositing the reflective film on thebase substrate and forming the reflective region around the opening areaof each sub-grating by a patterning process comprises: depositing areflective film on the substrate; spinning coating a photoresist film onthe reflective film; and exposing the opening area of each sub-gratingby performing an exposure, developing and etching processes to the basesubstrate and then removing the remaining photoresist on the basesubstrate.
 14. The method according to claim 13, wherein before spinningcoating the photoresist film on the reflective film, the method furthercomprises: stamping the reflective film by a mold with prism patterns toform a prism type reflective film.
 15. The method according to claim 12,wherein the substrate is a transparent substrate, an opposing substrateor an array substrate during the sequentially depositing a siliconnitride film on the base substrate.
 16. The method according to claim15, wherein a transparent conductive film is formed on the opposingsubstrate.
 17. The method according to claim 15, wherein if the basesubstrate is an array substrate, the method further comprises depositinga transparent conductive film on the array substrate before sequentiallydepositing the silicon nitride film on the base substrate.
 18. Thegrating sheet according to claim 12, wherein R sub-grating comprises:l=0.813 um, Φ=20%, t=80 nm, d=20 nm; G sub-grating comprises: l=0.813um, Φ=36%, t=60 nm, d=40 nm; and B sub-grating comprises: l=0.813 um,Φ=47%, t=40 nm, d=60 nm; wherein “l” is a period length of eachsub-grating, Φ is a duty cycle and Φ=w/l, “w” is an opening width ofeach sub-grating opening area, “t” is a thickness of the metal layer fordiffraction on the sub-grating, and “d” is an interval between theopening area and the reflective region.
 19. The grating sheet accordingto claim 12, wherein, a thickness of the metal layer of the Rsub-gratings is in the range of 75-85 nm; a thickness of the metal layerof the G sub-gratings is in the range of 55-65 nm; and a thickness ofthe metal layer of the B sub-gratings is in the range of 35-45 nm.